cacosh/csin failures on s390x since CORE-MATH integration

[Adhemerval Zanella Netto]

On 07/11/24 10:06, Mark Wielaard wrote:
> Hi,
> 
> Since the CORE-MATH integration the s390x buildbot shows the following
> 4 failures:
> 
> FAIL: math/test-float-cacosh
> FAIL: math/test-float-csin
> FAIL: math/test-float32-cacosh
> FAIL: math/test-float32-csin
> 
> https://builder.sourceware.org/buildbot/#/builders/glibc-fedora-s390x
> 
> Bunsen logs:
> https://builder.sourceware.org/testrun/8e8049073b623360f34a0f72e7bd0beb4ede3891?filename=math%2Ftest-float-cacosh.out
> https://builder.sourceware.org/testrun/8e8049073b623360f34a0f72e7bd0beb4ede3891?filename=math%2Ftest-float-csin.out
> https://builder.sourceware.org/testrun/8e8049073b623360f34a0f72e7bd0beb4ede3891?filename=math%2Ftest-float32-cacosh.out
> https://builder.sourceware.org/testrun/8e8049073b623360f34a0f72e7bd0beb4ede3891?filename=math%2Ftest-float32-csin.out
> 
> Cheers,
> 
> Mark

It is expected [1], I had to adjust it on x86, arm, and powerpc as well.
The __expm1 is exact for the input range, but due how csin/cacoshf
handles the expm1 result there is addition cancellation errors.

In this case someone will need to run 'make update-ulps' on a real
hardware and update the libm-test-ulps. 

[1] https://sourceware.org/pipermail/libc-alpha/2024-October/161131.html